A restrictive covenant is a type of real covenant

Real Covenant

A real covenant is a term used in real property law to describe a promise concerning the use of land. Real covenants are classified as either affirmative, a promise to do something or negative, a promise to not do something A real covenant is a term used in real property law to describe a promise...

, a legal obligation imposed in a deed

Deed

A deed is any legal instrument in writing which passes, or affirms or confirms something which passes, an interest, right, or property and that is signed, attested, delivered, and in some jurisdictions sealed...

 by the seller upon the buyer of real estate

Real estate

In general use, esp. North American, 'real estate' is taken to mean "Property consisting of land and the buildings on it, along with its natural resources such as crops, minerals, or water; immovable property of this nature; an interest vested in this; an item of real property; buildings or...

 to do or not to do something. Such restrictions frequently "run with the land" and are enforceable on subsequent buyers of the property. In jurisdictions that use the Torrens system of land registration, restrictive covenants are generally registered against title

Recording (real estate)

The vast majority of states in the United States employ a system of recording legal instruments that affect the title of real estate as the exclusive means for publicly documenting land titles and interests. This system differs significantly from land registration systems, such as the Torrens...

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Restrictive covenants may arise from many sources, and may be registered against titles or included in leases.